Vertical Cake

Hey everyone...had a question. I've got a few cakes coming up, its more of a team of us doing them. A big turkey day festivity at work. The theme they are using, which has nothing to do with thanksgiving by the way...is mardi gras.

Were doing 2 mad hatter hats but I'm not sure how to get the fondnat to stick in such a vertical manner. They will most likely be just for show cakes...no real "cake" involved.